The purpose of this Notice of Funding Opportunity (NOFO) is to invite R01 applications proposing research on palliative care across the lifespan for persons with serious illnesses and/or their care partners relevant to the missions of participating NIH Institutes, Centers, and Offices (ICOs), including projects focused on palliative care access, use, and quality. Applications may propose hypothesis-driven, milestone-defined palliative care traditional efficacy (Stage II), real-world efficacy (Stage III), effectiveness (Stage IV), and/or dissemination and implementation (Stage V) clinical trials in alignment with the NIH Stage Model (Stages II-V) and relevant Institute or Center policies. Applications may propose non-clinical trial palliative care research, such as health services research, methodologic research, natural experiments, or observational studies. Recipients will become members of the research community facilitated by the NIH-funded Advancing the Science of Palliative Care Across the Lifespan (ASCENT) Consortium. NOTE : This NOFO is not appropriate for applications proposing new intervention generation, refinement, modification, adaptation, and/or pilot testing (Stage I of the NIH Stage Model) clinical trial research. The intervention(s) to be tested must be in a developed and testable form, with Stage I activities already completed and demonstrated.